[R] as.numeric with tclvalue redux

[Peter Dalgaard]

Erin Hodgess wrote:
> Hi again R People:
>
> This works fine:
>   
>> library(tcltk)
>> a <- tclVar("4.5")
>> as.numeric(tclvalue(a))
>>     
> [1] 4.5
>   
>> #But if you have:
>> b <- tclVar("pi")
>> as.numeric(tclvalue(b))
>>     
> [1] NA
> Warning message:
> NAs introduced by coercion
>   
>
> Is anyone aware of a way around this, please?
>
>   
Brian already told you: Parse and eval.

 > eval(parse(text=as.character(tclvalue(tclVar("pi")))))
[1] 3.141593

(Beware: Depending on the environment in which you eval(), strange 
things can happen if you use the name of an internal variable in your 
function)

What happened with the Inf issue? I can't reproduce that:

 > as.numeric(as.tclObj("Inf"))
[1] Inf

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